A Brooklyn man – furious at his stepfather for breaking into his room to use his computer – stabbed him to death yesterday, police sources said.

The stepson, who shared the 13th-floor Dekalb Avenue apartment in Bedford-Stuyvesant with his alleged victim – went ballistic when he returned to the apartment at 3:20 p.m. and saw his bedroom door had been opened, the sources said.

He confronted his stepdad, which led to an argument that ended in bloodshed.

The 22-year-old pulled a knife and repeatedly stabbed his stepfather in the head, neck and shoulders, leaving a pool of blood in the apartment’s hallway, sources said.

The stepson, whose name was not released, then charged out of the apartment.

The 40-year-old victim, whose name was also withheld, died at Woodhull Hospital almost an hour later.